Warm, dry December puts state snowpack below average
Laura Lundquist
(Missoula Current) A noticeably warm and dry last quarter of 2024 has put most of Montana’s snowpack behind the curve. Hopefully, La Nina will arrive soon to turn that around before June.
The end of 2024 saw below-average snowpack in most of Montana’s mountain ranges, according to the U.S. Natural Resources Conservation Service. Only northwest Montana, including the lower Clark Fork River basin, and the Bears Paw Mountains have normal to above-normal snowpack for this time of year.
The upper Clark Fork basin has about three-quarters of its normal snowpack while the Bitterroot basin has 91%. The Tongue and Powder river basins in southeastern Montana have the least with 60-65% of normal snowpack.
Back in October, the National Oceanic and Atmospheric Administration predicted that a La Nina weather pattern - which normally means more snow for Montana - would arrive late in the year, December at the earliest. But December remained warm and dry, so during the last quarter of 2024, precipitation totals across the state were below-normal.
While the mountains got some snow, very little made it down to the valleys of western Montana.
According to National Weather Service records that date back to the 1890s, Missoula received only 0.4 inches of moisture when an inch is normal for December. Less than an inch of snow settled on Missoula during December, the second lowest amount on record. Part of the reason is December was so warm: it was the eighth warmest December on record for Missoula. The mean temperature was 31.7 degrees Fahrenheit, more than 8 degrees above normal.
Farther north, Kalispell received an inch of moisture, and 3 inches of snow fell during December. But the mean December temperature of 31.3 degrees was only slightly lower than Missoula’s mean and it was the fourth warmest December on record for Kalispell. At a mile high, Butte is regularly colder than Missoula, but its mean December temperature of 28.5 degrees was 9.5 degrees above normal and it received no snow in December.
River flows are often at their lowest during the fall. But, after a dry summer and fall, many rivers are even lower than normal. The Clark Fork River above Missoula was flowing at 1,000 cubic feet per second on New Year’s Eve, more than 200 cfs below average. Likewise, the Blackfoot River, which hit historic lows this summer, had 400 cfs when it should be 500 cfs. The Bitterroot River was also about 100 cfs less than it should be.
However, January appears to be turning things around. The first decent snowfall hit the lawns of Missoula on New Year’s Day and the Missoula International Airport had received 0.7 inches of precipitation by Sunday evening, more than fell during the month of December.
The National Weather Service monthly outlook predicts slightly colder temperatures for northeastern Montana while western Montana might be slightly warmer. But the whole state is predicted to see above-normal precipitation.
The three-month outlook predicts that the above-normal precipitation could continue through the end of March while temperatures across the state will finally dip below normal. So snowpack totals might start catching up over the next few months.